The present invention is directed to a circuit interrupter using a minimum of dielectric liquid and more specifically to an interrupter as above where the liquid is substantially maintained in that state under all operating conditions.
Several liquid sulphur hexachloride (SF.sub.6) circuit breaker designs were developed in the late 1950s as, for example, illustrated in Leeds et al U.S. Pat. No 3,150,245. The difficulty with the Leeds design was that because of the low critical temperature (114.degree. F.) of a typical dielectric liquid such as SF.sub.6 the storage vessel had to be designed for a pressure of 2,000 psi. Critical temperature is defined as that temperature above which increases in pressure will not liquify the gas. Moreover, many times the interrupter also had to be designed for both the gas and liquid phases because of this low critical temperature.
As disclosed in copending application Ser No. 818,004, filed July 22, 1977, entitled "Circuit Interrupter Using Dielectric Liquid With Energy Storage" and assigned to the present assignee the use of dielectric liquid such as SF.sub.6 to extinguish arcs in an interrupter is disclosed. A similar type structure is also disclosed.